Spectrophotometric research of reaction of complex formation 3-hydrazono-6-(3,5-dimethyl-pirazol-1-il)-1,2,4,5-tetrazine with Cu2+, Ni2+, Mn2+ was carried out. Based on the data of UV and visible region spectroscopy the coordination compounds of tetrazine with salts of metals were synthesized. The simulation the structures of the synthesized complexes was conducted. It has been shown that calculated IR spectra are in good agreement with the experimentally obtained ones.